Tunnel and electrostatic coupling in graphene-LaAlO3/SrTiO3 hybrid systems

• Main Authors: I. Aliaj, I. Torre, V. Miseikis, E. di Gennaro, A. Sambri, A. Gamucci, C. Coletti, F. Beltram, F. M. Granozio, M. Polini, V. Pellegrini, S. Roddaro
• Format: Article
• Language: English
• Published: AIP Publishing LLC 2016-06-01
• Series: APL Materials
• Online Access: http://dx.doi.org/10.1063/1.4953821
• ISSN: 2166-532X

We report on the transport properties of hybrid devices obtained by depositing graphene on a LaAlO3/SrTiO3 oxide junction hosting a 4 nm-deep 2-dimensional electron system. At low graphene-oxide inter-layer bias, the two electron systems are electrically isolated, despite their small spatial separation. A very efficient reciprocal gating of the two neighboring 2-dimensional systems is shown. A pronounced rectifying behavior is observed for larger bias values and ascribed to the interplay between electrostatic field-effects and tunneling across the LaAlO3 barrier. The relevance of these results in the context of strongly coupled bilayer systems is discussed.